But a US healthcare provider, CVS CareMark, has just announced it is dropping the film version of Suboxone from the list of medicines available under its insurance cover, prompting new fears about the treatment's future growth. The news sent Reckitt down 252p or 5% to £46.77, making it the biggest faller in the FTSE 100 yesterday.

Credit Suisse analyst Charlie Mills put a neutral rating on the company but cut his price target from £49 to £46.50. He said:

CVSC clearly appears to have decided that film and tablet are effectively the same product and so is steering its customers to the cheaper [generic] version...It is hard to see others won't follow suit (though we have no evidence this has happened yet). This opens the prospect of Reckitt losing not only the cash payers for Suboxone, but also a decent proportion of those on insurance plans as well. We estimate 15% of Suboxone users pay cash, 10% Medicaid, 70% third party insurance, 5% others.

How to model this is far from an exact science, but we will assume 50% of the insured patients are lost in 2014, along with all the cash buyers. This is materially worse than we had before, with a 5% cut to 2014 earnings, and 10% in 2015 (when all insured patients are lost, leaving just Medicaid/others). We cut our valuation for Suboxone to £1.1bn (was £2.9bn). The [remainder of Reckitt] we believe is in better shape and trading well, but if Suboxone is only worth £1.1bn then the implied PE on the rest is 20.5 times (2014), and is beginning to look rather fully valued.

Overall, with further comments from US Federal Reserve chairman Ben Bernanke playing down fears of an early end to its bond buying programme, markets recorded another positive week. There was a touch of caution yesterday as Chinese officials hinted at lower than expected economic growth, while in the eurozone Portugal's continuing political crisis sent its bond yields sharply higher.

Michael Hewson, senior market analyst at CMC Markets, said:

It would appear that comments from the Chinese finance minister that the world's second biggest economy could well miss its growth target for this year have taken some of the edge off the exuberance of the last two days though core European equity markets continue to remain underpinned on the prospects for continued central bank support from the Federal Reserve.

Southern Europe has been another story entirely with Portuguese markets getting hit on political uncertainty there, and the Spanish IBEX being hit by talk of a new energy bill which will raise prices to consumers as a part of electricity sector reform with the government slashing subsidies on renewables.

So the FTSE 100 finished at 6544.94, up just 1.53 points on the day but almost 170 points ahead over the week.

Banks were in the spotlight, with growing talk that a sale of shares in Lloyds Banking Group could happen sooner rather than later.

At the start of the week Singapore sovereign wealth fund Temasek and a consortium of institutional investors were both said to have approached the UK government about buying part of its stake in Lloyds.

Then came reports that up to 5% of Lloyds' shares - worth up to £5bn - could be sold to institutions in September, a few weeks after its interim results. This would be following by a sale of another chunk of the government's stake to retail investors. Gary Greenwood at Shore Capital said:

[Selling shares to the public] may be politically astute but could be difficult to execute, in our view. However, whatever the ultimate outcome is, we think the government will be careful to ensure that an initial share sale is structured to avoid any potential overhang, thus damaging the prospect for future sales.

We believe news of a planned share sale could coincide with or come soon after the company announces its interim results on 1 August. We expect these results to have an upbeat tone given the recently strengthened capital position of Lloyds (following a series of asset disposals) and given the improving outlook for the UK economy and housing market. We also expect firmer guidance on plans to resume dividend payments to ordinary shareholders, with our forecasts now assuming a 1.5p final dividend will be proposed this year.

Lloyds closed 1.48p higher at 67.73p while the other taxpayer controlled bank, Royal Bank of Scotland, rose 0.4p to 304.4p.

Insurer Resolution climbed 10.5p to 318.5p after Nomura raised its rating from reduce to neutral and its target price from 250p to 311p, while ITV added 3.9p to 157.9p as Exane BNP Paribas put an outperform rating on the broadcaster with a 170p target.

But with talk of a Chinese slowdown, the week's revival in commodity companies went into reverse yesterday. Mexican silver miner Fresnillo fell 37p to 981p while Anglo American dropped 42.5p to 1294.5p.

Experian dipped 16p to £11.83 on profit taking after the credit data specialist said it was on track to meet its growth targets for the year.

British American Tobacco and Imperial Tobacco failed to benefit from yesterday's news that the government had postponed plans to introduce plain packaging for cigarettes. Instead investors noted reports the companies could be interested in a possible bid for cigar and snuff specialist Swedish Match, as they seek expansion to make up for a declining market for traditional cigarettes.

Another competitive threat comes from electronic cigarettes, which vaporise nicotine to give users their fix without smoke or carcinogenic risks. Earlier in the week Canaccord Genuity said e-cigarettes would be the most significant development in the history of the tobacco industry:

We estimate the e-cigarette market will grow from $2bn in 2012 to $3bn in 2013 (tobacco is approximately $700bn). In the longer term, the total combined market will shrink at a more rapid rate than most investors envisage as e-cigarettes wean smokers off tobacco, but do not attract new users into the overall category.

It tipped BAT, down 19p at £34.76, as being better prepared for e-cigarettes than Imperial, 23p lower at £22.50. Meanwhile Swedish Match added nearly 6%, valuing the business at around £5bn.

Finally, Oxford Instruments closed 120p higher at £13.70 after a positive update from the technology group, which showed improving orders, sales and profits in the third month of the first quarter after a slow start to the year. Analyst Scott Cagehin at Numis Securities said:

We believe that the shares should start to trade higher after recent weakness and retain our positive stance as we believe that Oxford is a high quality business that possesses defensive characteristics. Structural demand for Oxford's product portfolio is apparent and we believe that these factors, along with new products, technology upgrades and market share gains, position Oxford strongly to grow in excess of general global GDP growth.

Demand for Oxford's products is being driven by the shift to smaller applications and the ability to analyse and manipulate matter at the atomic level. As a consequence, nanotechnology research is growing strongly with funding levels expected to increase between 10%-20% per annum, creating a good platform for growth. Additionally, industrial facing hand-held applications are set to enjoy good demand, with increasing requirements from industry to analyse on the ground, increase productivity and comply with tighter regulatory testing requirements.